<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>按字母表顺序输出字母</title>
</head>
<body>
<script>
  function alphabetSort(message){
    return message.split('').sort().join('');// wirte your code here
  }
  document.write(alphabetSort('hello')); // should return 'ehllo'
</script>
</body>
</html>